Teleprinters and other printers often record information on an elongated paper web rather than on individual sheets. Usually, in such a printer, the paper is advanced by a short line space increment following printing of each line; more rarely, the web may be advanced continuously during printing. The printer frequently prints two webs simultaneously. In many instances it is desirable to store one paper web in continuous, uncut form for record purposes.
One problem in a printer paper take-up and storage device for a printer that records on a paper web is a tendency toward skewing of the paper web due to imbalance between the forces on the paper traversing the printer and the forces applied to the web by the take-up device. Another problem occurs in printers that provide for last-character visibility by advancing a short length of the web from the printer, and require a corresponding reverse movement of the paper back into the printer to resume printing, as in the printer of Mero et al. U.S. Pat. No. 3,844,395. If the reverse movement of the paper web encounters appreciable resistance from a take-up device a printer malfunction is virtually certain, particularly when the printer uses the usual friction feed arrangement employing a roller platen.
Yet another difficulty relating to a printer paper take-up and storage device results from the fact that a variety of different width papers are used, even in the teleprinter field alone. To form tight rolls suitable for storage, a take-up device should afford accurate guidance for the paper edges. Thus, for many paper winders, there must be a separate model for each possible paper width.
In the operation of any web printer, the paper web ultimately runs out. Moreover, the paper web may break during recording. In either case, any paper take-up and storage device should function to wind up the paper web and then shut down to avoid overheating of the take-up drive motor. Connecting the new paper web to the take-up and storage device should be simple and convenient to minimize down-time for the printer.